Phosphodiesterase 1 (orthophosphoric diester phosphohydrolase, EC 3.1.4.1; herein “PDE-1”) is an enzyme that catalyses the hydrolysis of a phosphodiester bond at the 3′ hydroxyl end of ribopolynucleotide to yield a 5′ ribonucleotide.
PDE-1 is particularly important to food and pharmaceutical industries because the 5′ ribonucleotides produced by PDE-1—mediated cleavage of yeast RNA are useful as flavour enhancers.
Barley cells or rootlets are used in the food industry as a source of PDE-1.
The processes for purification of PDE-1 from barley rootlets tend to be difficult to operate on a commercial scale, in terms of requiring sophisticated extraction and separation techniques, multiple steps and expensive reagents and equipment. Some processes are characterised by an unacceptable loss or wastage of PDE-1. Other processes tend to produce a final product that has a sub-optimal specific activity.
In view of the above, there is a need for improved processes for purification of PDE-1.